Utah collection laws

I received a letter in the mail stating i owed verizon wireless 565.00 dollars for cell phone service in 2009. I never had a verizon wireless services i told that to the guy from Afni collection agency he told me there is two ways to take care of this bill just pay us or send us proof you didnt have this service. But yet verizon wireless has the fraud papers i signed and the police report filed. This guy thinking he is the mafia says to me just pay us! Well i have news for everybody online this agency is being investigated by the government for fraud!